Bundle of stacked bags



Sept. 16, 1969 w. L. CALVERT 3,467,249

BUNDLE OF STACKED BAGS Filed Aug. 29, 1966 2 Sheets-Sheet 1 INVENTOR.

WILLIAM L ./C{\LVERT BY a c ATTORN w. L. CALVERT 3,467,249

BUNDLE 0F STACKED BAGS Sept. 16, 1969 2 Sheets-Sheet 2 Filed Aug. 29, 1966 F c a B,

flux?- United States Patent 3,467,249 BUNDLE 0F STACKED BAGS William L. Calvert, Westfield, N.J., assignor to Union Carbide Corporation, a corporation of New York Filed Aug. 29, 1966, Ser. No. 575,872 Int. Cl. B65h 55/00, 75/02; B65d 85/04 US. Cl. 206-57 4 Claims ABSTRACT OF THE DISCLOSURE A bundle configuration for stacking bags having a general W cross-sectional shape.

This invention relates to a bundle for bags and a method and apparatus in connection therewith, and more particularly, to a bundle configuration for bags having slippery surfaces.

Heretofore, the manufacture, palletizing, storage, shipment, and use of thermoplastic industrial shipping bags has been handicapped by the lack of suitable packing configuration or method. The square-ended polyethylene bag, in particular, because of its inherent slipperiness and its variation in thickness when folded flat, has frustrated all efforts to form a stable and dense bundle or pallet load. Such bags, as they are delivered from the fabricating machine, slide into disorderly piles; they are then manually counter, organized into piles, and placed in a carton or box on a pallet. Furthermore, the pallet load, when strapped, develops a convex upper surface which prevents stable stacking when stored in a warehouse, for example. Bags arrive, after shipment to the users location, in a disorderly array; and, when stacked at the bag filling location, the bags cause inconvenience to the operator by failing to remain in an orderly stack. Manufacturing economy and customer acceptance are, therefore, both jeopardized by the lack of a satisfactory packaging system.

The present invention provides a bundle configuration for bags of the aforementioned type wherein bundle stability, high bag content per bundle, and uniform high bundle density are achieved.

The present invention provides a method and apparatus for forming a bundle configuration particularly but not exclusively suitable for bags which have slippery surfaces. In accordance with the method, a plurality of bags are stacked such that a face of one bag rests on a face of an adjacent bag. The bags are retained in a stack whereby the ends of each bag lie substantially in a plane and are superimposed upon corresponding ends of an adjacent bag. The central portion of each bag is forced in a direction substantially perpendicular to the plane of the bag ends such that the thickness of the central portion, measured perpendicular to the plane of the bag ends, is approximately equal to the thickness of the bag ends. The resulting protruding center portion of the stacked bags is then pressed inwardly towards the stacked bags while the ends of the bags are retained such that the bundle assumes a general W shape. This is followed by strapping, tying, wrapping or bagging the stacked bags such that the bags form a stable bundle which can be stacked on similarly formed bundles.

A further aspect of the present invention includes an apparatus for forming a bundle of bags such that the bundle has the aforementioned W configuration. The apparatus comprises a housing; means for retaining a plurality of bags in stacked fashion in the housing whereby the ends of each bag are superimposed upon corresponding ends of an adjacent bag; forming means for the stacked bags adapted to displace the central region of the stacked bags in a direction substantially perpendicular to 3,467,249 Patented Sept. 16, 1969 ice the plane of the bag ends; and means for subsequently pressing the protruding center region inwardly towards the stacked bags while the ends of the bags are retained to form a W shaped bundle.

The invention further includes a bundle configuration particularly but not exclusively suitable for bags having slippery surfaces; the bundle has a generally rectangular shape bounded by two opposing planar surfaces two opposing side planes, and two opposing end planes; and it is further characterized in that intermediate the opposing side planes there is defined at least a first channel which is vertically disposed from one of the planar surfaces to a point intermediate the opposed planar surfaces and which channel extends from one end plane to the other end plane. Intermediate the opposed side planes there is further defined at least two other channels which are vertically disposed from the other of the planar surfaces in a direction opposite to the first channel to a point intermediate the opposed planar surfaces and which two channels extend from one end plane to the other end plane such that the cross section of the bundle assumes a general W shape.

In the drawing:

FIG. 1 is an isometric view of a bundle configuration for bags illustrating a preferred embodiment of the invention.

FIG. 2 is an isometric view of a manual bag bundling apparatus embodying the invention.

FIG. 3 is an elevational view in cross-section of a bag illustrating its position when placed over the inverted V-former of FIG. 2.

FIG. 4 is a front elevational view, partly in section, of an automatic bag bundling apparatus constituting a further embodiment of the invention illustrating a stage of operation in broken lines.

FIG. 5 is a view of the device of FIG. 4 illustrating one stage of operation.

FIG. 6 is a view of the device of FIG. 4 illustrating a still further stage operation.

FIG. 7 is an elevational view partly in section of the entrance port of a forming tunnel illustrating the bags positioned therein.

FIG. 8 is an elevational view of the exit port of the forming tunnel of FIG. 7 illustrating the bags positioned therein.

Referring now to the drawing, as shown in FIG. 1, the present invention includes a bundle 10 having two opposing end planes 12, 14, two opposing side planes 16, 18, and two opposing planar surface areas 20, 22. Intermediate the side planes 16, 18 there is defined a first channel 24 which extends vertically from the lower planar surface 22 to a level 26 intermediate the opposed planar surface 20 and 22. The channel 24 extends from end plane 12 to end plane 14. Intermediate the side planes 16, 18 there are further defined two other channels 28, 30 which extend vertically from top planar surface 20 in a direction opposite to channel 24 to a level intermediate planar surfaces 20, 22. Also, the channels 28, 30 extend from end plane 12 to end plane 14. The bundle 10 is further provided with straps 32, 34 which fit securely about the surfaces 20, 22 and the side planes 16, 18. The straps 32, 34 can be fabricated from thermoplastic material, metal, rope, and the like. In the alternative, however, the bundle can be tied, wrapped or bagged as opposed to strapping. It should be noted that the convolution 36 of the mid-section of the bags causes the density of the center of the bundle 10 to approximately equal the density of the stacked up bag ends at the extremities of the bundle 10. It should further be noted that channel 24 allows the bundle 10 to be placed over a vertical blade which can 'be bounded by pegs and the like at the users station so 3 that the bundle will remain stabilized after its straps have :been removed.

The exact form of the bundle 10 can be further defined by describing a preferred manual method for forming the bundle. For instance, FIG. 2 shows a manual apparatus which consists of an open-topped box 40 with an inverted V-shaped former 42 extending upwardly from the center of its bottom surface 44. An end 46 of the box 40 has a matching V-shaped cutout 48 to permit horizontal withdrawal of the former 42. FIG. 3 shows the cross-sectional shape of a bag laid over the V-shaped former 42 in the forming box 40. The angle of the V FIG. 3) is calculated to be such that when the bag 50 is laid over the former 42, as shown in FIG. 3, the thickness of the center region (t') of the bag 50 measured vertically will be equal to the vertical thickness of the bag end (t). The height of the V 42 can be adjusted to accommodate the length of the bags being stacked.

To form a bundle 10, straps 32, 34 are laid transversely across the bottom 44 of the box 40 with their ends ex tending up and over the sides 52, 54. The former 42 is then inserted through the V-shaped cutout 48, passing over the top of the straps 32, 34; and the bags are placed in the box 40 over the former 42 with their ends stacked horizontally in the areas between the sides 52, 54 of the box 40 and the inverted V-former 42. When the desired number of bags have been assembled, the former 42 is removed horizontally through the V-shaped cutout 48 and the top of the pile of bags is pressed down, with a flat platen for example, to force the upwardly protruding portion of the pile downward into the cavity formed by the withdrawal of the former 42. Thereupon, the straps 32, 34 are brought up over the top of the bundle 10 (FIG. 1) and tightly secured by tying, clamping or sealing. A conventional box strapper can be used for tightening and securing the straps. When removed from the box 40, the bundle 10 will possess a shape approximately as shown in FIG. 1.

The bundle 10 can also be formed automatically. FIGS. 4 through 8, inclusive, illustrate the preferred apparatus for the automatic formation of the bundle 10. in FIG. 4, a chamber 56 in which the bags 50 are stacked is bounded on both sides by side plates 58, 60. Bags are prevented from falling out of the bottom by a series of fork tines 62 and the bags are weighted down by a floating platen 64 which is guided by rollers 66. The floating platen 64 performs the same function as the V-former 42 referred to in the discussion of the manual apparatus (FIG. 2). However, whereas the V-former is convex upward in the case of the manual apparatus, the V-former in the automatic equipment is convex downward. Furthermore, the apex of the V has been omitted in order to define a slot 68. An alternate bottom support for the stack of bags is provided in the form of two trap doors 70 which can be rotated into the positions shown in FIG. 6.

Immediately below the stacking chamber 56 is shown a bag 50, draped between two rails 72, and with the bag ends 38, 39 hooked over the rails. This is the position occupied by a bag at the completion of the fabrication operations. Pickup fingers 74, with their actuating linkages 76 are equipped with suction cups 78 to grip the bag ends and elevate the bag into the underside of the stacking chamber 56. The bag 50 and lift fingers 74 are shown in a partially elevated position in dotted lines.

In the method of the invention, the lift fingers 74, with their suction cups 78 are pressed against the bag ends 38, 39 and lift the bag 50 toward the stacking chamber 56 as indicated by the dotted view of FIG. 4. When the bag 50 has been pressed into the bottom of the stacking chamber 56, the fork tines 62 are withdrawn, as shown in FIG. 5. The fork tines 62 which have been withdrawn from above the newly placed bag, are then returned to their initial position but under the newly placed bag. The lift fingers 74 then return to their lower position to pick up the next bag. It should be noted that the fork tines 62 are so longitudinally spaced that they will intermesh and not interfere with the lift fingers 74.

When placement of the desired number of bags in the stacking chamber 56 has been completed which can be determined by a commercial electric counter, the trap doors 70 swing closed; and the fork tines 62 are withdrawn, as shown in FIG. 6. A pushing device (not shown) can be used to transfer the stack of bags 51 from the stacking chamber 56 into one end of a forming tunnel 80. FIG. 7 shows the cross-sectional shape of the forming tunnel 80 at its entrance port, while FIG. 8 shows the cross-sectional shape of the forming tunnel 80 at its discharge port. The surfaces 82, 83 which bound the tunnel 80 taper smoothly from one shape to the other. More specifically, the tunnel 80 has a converging shape such that the opening at its entrance port (FIG. 7) is larger than the opening at its exit port (FIG. 8). The entrance port is so shaped to receive the bundle of the bags as stacked, and the exit port is shaped so as to have the shape of the bundle desired. As shown in FIG 7, surface 83 has a projection 79 which is channeled 85 and which is adapted to receive the convolution 36 of the mid-section of the bags as they enter the tunnel 80. This projection 79 decreases in depth as the exit port of the tunnel is approached such that, at the exit port, the projection 79 tapers into surface 83 (FIG. 8). Surface 83 is also provided with at least two parallel blades or rails 84, 87 (FIG. 8) which extend vertically into the tunnel 80. The blades 84, 87 increase in size as the projection 79 decreases, and form the channels 28, 30 of the bundle of FIG. 1. The decreasing in size of the projection 79 causes the convolution 36 of the mid-section of the bags to move into the tunnel 80 and thus substitutes as the flat pressing platen described above with respect to the manual method. Thus, as the bundle of bags 51 is pressed through the tunnel 80, its shape is transformed from that shown in FIG. 7 to the shape shown in FIG. 8. As the bundle 51 exits from the discharge port of the tunnel 80 in the shape shown in FIG. 8, it is tightly strapped with polypropylene strapping 32, 34 (FIG. 1) applied by an automatic strapping machine. It can alternately be manually strapped, tied or inserted into a paper or plastic sack.

Thus, a bundle configuration can be formed wherein both stability and high density are readily achieved. When placed in a palletized box the bundles form a load which is better shaped, contains more bags, is stackable and remains neatly organized during shipment. The stability of the pile, the fact that all bags in the bundle are identically oriented and the fact that each bundle contains a pre-counted number of bags all constitute significant advantages for the user. The greatest economic advantage to the manufacturer stems from the fact that the bundle configuration lends itself to semi-automatic or fully automatic forming and strapping. Further economies result from the greater density of pallet loads and more stable stacking of pallets in warehouse or transportation vehicle.

The dimensions of the bundle can be varied as long as a practical and easily handled bundle is produced and variations can be made in the orientation of the forming operation throughout the range from horizontal to vertical. Slight or minor tapers and slopes of the boundaries of the forming chamber can be made without extending beyond the scope of the invention. Furthermore, the bundle configuration and forming method of the present invention are also applicable to bags which differ somewhat in form or material from the square-ended polyethylene industrial valve bag.

What is claimed is:

1. A bundle configuration for stacking bags, said bundle configuration having a general rectangular shape bounded by two opposing planar surfaces, two opposing side planes, and two opposing end planes, said bundle configuration being characterized in that intermediate the opposing side planes there is defined at least a first channel which is vertically disposed from one of said planar surfaces to a point intermediate said opposed planar surfaces and which channel extends from one end plane to the other end plane, and intermediate the opposed side planes there are further defined at least two other channels which are vertically disposed from the other of said planar surfaces in a direction opposite to said first channel to a point intermediate said opposed planar surfaces and which two channels extend from one end plane to the other end plane such that a bundle having a general W shape is formed.

2. The bundle configuration of claim 1 wherein said two defined channels are parallelly disposed with respect to each other in said planar surface.

3. The bundle configuration of claim 2 wherein said two defined channels are angularly disposed toward each other intermediate said opposed planar surfaces.

4. The bundle configuration of claim 3 wherein said bundle is provided with a plurality of strapping means adapted to fit securely about the planar surfaces and opposing side planes thereof.

References Cited UNITED STATES PATENTS 3,346,104 10/1967 Marsh 206--57 FOREIGN PATENTS 619,613 10/1935 Germany. 1,081,823 5/1960 Germany.

WILLIAM T. DIXSON, 111., Primary Examiner US. Cl. X.R. 

